【转】使用Spring Data来操作MongoDB（单实例）(2)

 创建Spring context。将所有spring beans和mongodb对象都声明在Spring context文件中，这里创建的是applicationContext.xml文件。注意到我们并没有创建一个叫做"nature"的数据库。在第一次存储数据的时候MongoDB将会为我们创建这个数据库。

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
	xsi:schemaLocation="http://www.springframework.org/schema/beans

http://www.springframework.org/schema/beans/spring-beans-3.0.xsd


http://www.springframework.org/schema/context

        http://www.springframework.org/schema/context/spring-context-3.0.xsd">

	<bean id="natureRepository"
		class="com.orangeslate.naturestore.repository.NatureRepositoryImpl">
		<property name="mongoTemplate" ref="mongoTemplate" />
	</bean>

	<bean id="mongoTemplate" class="org.springframework.data.mongodb.core.MongoTemplate">
		<constructor-arg name="mongo" ref="mongo" />
		<constructor-arg name="databaseName" value="nature" />
	</bean>

	<!-- Factory bean that creates the Mongo instance -->
	<bean id="mongo" class="org.springframework.data.mongodb.core.MongoFactoryBean">
		<property name="host" value="localhost" />
		<property name="port" value="27017" />
	</bean>

	<!-- Activate annotation configured components -->
	<context:annotation-config />

	<!-- Scan components for annotations within the configured package -->
	<context:component-scan base-package="com.orangeslate.naturestore">
		<context:exclude-filter type="annotation"
			expression="org.springframework.context.annotation.Configuration" />
	</context:component-scan>

</beans>

创建一个测试类。这里我已经创建了一个测试类，并通过ClassPathXmlApplicationContext来初始化他。

package com.orangeslate.naturestore.test;

import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.orangeslate.naturestore.domain.Tree;
import com.orangeslate.naturestore.repository.NatureRepositoryImpl;
import com.orangeslate.naturestore.repository.Repository;

public class MongoTest {

	public static void main(String[] args) {

		ConfigurableApplicationContext context = new ClassPathXmlApplicationContext(
				"classpath:/spring/applicationContext.xml");

		Repository repository = context.getBean(NatureRepositoryImpl.class);

		// cleanup collection before insertion
		repository.dropCollection();

		// create collection
		repository.createCollection();

		repository.saveObject(new Tree("1", "Apple Tree", 10));

		System.out.println("1. " + repository.getAllObjects());

		repository.saveObject(new Tree("2", "Orange Tree", 3));

		System.out.println("2. " + repository.getAllObjects());

		System.out.println("Tree with id 1" + repository.getObject("1"));

		repository.updateObject("1", "Peach Tree");

		System.out.println("3. " + repository.getAllObjects());

		repository.deleteObject("2");

		System.out.println("4. " + repository.getAllObjects());
	}
}

 最后，让我们以Java应用程序的方式运行这个示例，我们可以看到如下的输出。第一个方法存储了一个"Apple Tree"。第二个方法存储了一个"Orange Tree"。第三个方法通过id获取一个对象。第四个使用Peach Tree更新对象。最后一个方法删除了第二个对象。

1. [Person [id=1, name=Apple Tree, age=10, category=null]]
2. [Person [id=1, name=Apple Tree, age=10, category=null], Person [id=2, name=Orange Tree, age=3, category=null]]
Tree with id 1Person [id=1, name=Apple Tree, age=10, category=null]
3. [Person [id=1, name=Peach Tree, age=10, category=null], Person [id=2, name=Orange Tree, age=3, category=null]]
4. [Person [id=1, name=Peach Tree, age=10, category=null]]

 注：可以在GitHub上下载到源码。